It's one of the better 4X space games if you're more of a builder than a fighter. The economic meta is fun, building space stations and trade/mining fleets. Combat is limited by wonky AI. However the game is pretty genericised. All faction interactions, station layouts, and experiences are more or less the same with only minor aesthetic variations. The DLC balloons the cost to the point that you think you're getting a Paradox game but every country is Germany. I pirated it and wouldn't buy it unless it's on deep discount.

edit: The exploration is also generic. Every sector feels more or less the same with few exceptions in the form of sectors that damage your ship. There are just ones with resources and ones with multiple adjacent factions that sometimes clash.

i have put a good number of hours into and really enjoyed x4 over the years
if you have never played an x game before, it will take a bit of getting used to, but i think it's the best one to start with
expect a certain degree of mild jank and a very... idiosyncratic... menu system
it's not terrible by any means, but it certainly takes some getting used to

though it does have a story (kinda, though the expansions might have added to it), it is 99.9% a sandbox game
if you want to run a business empire in space, but also bum around in a ship at the same time, there is nothing better

That's what I look like when I get so drunk the chair tips over backwards.

X3: Reunion is real fun, that's the only one I've played.